Reducing NFAs by invariant equivalences
نویسندگان
چکیده
منابع مشابه
Reducing NFAs by invariant equivalences
We give new general methods for constructing small non-deterministic 4nite automata (NFA) from arbitrary ones. Given an NFA, we compute the largest right-invariant equivalence on the set of states and then merge the equivalent states to obtain a smaller automaton. When applying this method to position automata, we get a way to convert regular expressions into NFAs which are always smaller than ...
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The efficiency of regular expression matching algorithms depends very much on the size of the nondeterministic finite automata (NFA) obtained from regular expressions. Reducing the size of these automata by using equivalences has been shown to reduce significantly the search time. We consider the problem of reducing the size of arbitrary NFAs using equivalences and preorders. For equivalences, ...
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We study the NFA reductions by invariant equivalences. It is well-known that the NFA minimization problem is PSPACE-complete. Therefore, there have been approaches to reduce the size of NFAs in low polynomial time by computing invariant equivalence and merging the states within same equivalence class. Here we consider the nondeterminism reduction of NFAs by invariant equivalences. We, in partic...
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A result of Nicaud states that the number of distinct unary regular string languages recognized by minimal deterministic finite automata (DFAs) with n states is asymptotically equal to n2n−1. We consider the analogous question for symmetric difference automata (Z2NFAs), and show that precisely 22n−1 unary languages are recognized by n-state minimal Z2-NFAs.
متن کاملFactorization of Fuzzy Automata
We show that the size reduction problem for fuzzy automata is related to the problem of solving a particular system of fuzzy relation equations. This system consists of infinitely many equations, and finding its general solution is a very difficult task, so we first consider one of its special cases, a finite system whose solutions, called right invariant fuzzy equivalences, are common generali...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2003
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(03)00311-6